Express your answer as a mixed number simplified to lowest terms. $12\dfrac{15}{19}-4\dfrac{12}{19} = {?}$
Answer: Separate the whole numbers from the fractional parts: $= {12} + {\dfrac{15}{19}} - {4} - {\dfrac{12}{19}}$ Bring the whole numbers together and the fractions together: $= {12} - {4} + {\dfrac{15}{19}} - {\dfrac{12}{19}}$ Subtract the whole numbers: $=8 + {\dfrac{15}{19}} - {\dfrac{12}{19}}$ Subtract the fractions: $= 8+\dfrac{3}{19}$ Combine the whole and fractional parts into a mixed number: $= 8\dfrac{3}{19}$